Impact of High-Temperature Storage on Capacity Fade of Ni-Rich Cathodes in All-Solid-State Batteries

Despite the extensive research efforts focused on enhancing the lifespan and energy density of all-solid-state batteries, the calendar aging behavior of cathode material within the all-solid-state batteries system continues to be underexplored. In this study, we elucidate the capacity fade behavior of Ni-rich cathodes in all-solid-state batteries after high-temperature storage using electrochemical techniques, synchrotron X-ray-based characterization tools, and electron microscopy. High-temperature storage degrades the electrochemical performance of the Ni-rich cathode, constraining the capacity for charging and discharging the electrode. A larger portion of capacity loss is attributed to extensive charge fading, resulting from structural reconstruction on the cathode surface during high-temperature storage. The application of a LiNbO 3 coating layer effectively inhibits the interfacial degradation, virtually eliminating both types of fading. These findings offer a deeper understanding of the storage-induced capacity fades of Ni-rich cathodes in ASSBs.